Science Of Wint-O-Green LifeSavers NPR investigates the scientific mystery of the spark emitted by chewing Wint-O-Green Life Savers mints.

Why Do Wint-O-Green Life Savers Spark In The Dark?

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IRA FLATOW, BYLINE: Susan, I've been saving this story just for this point. Sometimes, we come across very unusual stories in our travels. And a few months ago, I got a letter from a listener who wrote, my children - my teenage children - have been going into the closet a few times a day. And I've been wondering about what was happening to them, whether some hanky-panky or whatever was going on in the closet. And I finally asked them, and they said, Mom, we're not doing anything wrong. We're just chewing on LifeSavers.



FLATOW: And now, you know, being a modern mother, I thought there was something not very unusual about that, but certainly...

STAMBERG: Peculiar.

FLATOW: Peculiar and worthy of investigation.


FLATOW: So I'm writing you to find out what is happening with Wint-O-Green LifeSavers. The kids tell me that when you chew on them, they give off a glow, something like a spark or a sparkle.


FLATOW: And...

STAMBERG: And so they go into a dark closet to sit and chew on Wint-O-Green LifeSavers and look at the sparks?

FLATOW: Two people go into the closet. One person chews on the LifeSaver.

STAMBERG: (Laughter).

FLATOW: It gives off a spark. They trade positions, trade LifeSavers, and another one chews on it.

STAMBERG: Sounds fishy to me. Did you try to track this down at all?

FLATOW: I tried to track it down. And I went so far as to buy us each pack of LifeSavers.

STAMBERG: Well, did you call the LifeSaver people or anything?

FLATOW: I called them, and they said they've heard about this for 30 or 40 years. This is not something new. They don't know why this happens, but they suspect there's some chemical reaction in the Wint-O-Green ingredient because it only happens with Wint-O-Green LifeSavers.

STAMBERG: Oh, it doesn't happen with cherry LifeSavers...


STAMBERG: ...Or Pep-O-Mint LifeSavers?

FLATOW: Only with Wint-O-Green. And the mechanical action of your teeth crunching creates some sort of voltage inside the LifeSaver or some sort of chemical reaction that gives off this burst of light.

STAMBERG: So you brought us each a pack of LifeSavers, but what should we do? Sit in here and chew them? It's a bright room.

FLATOW: I say let's go into the closet and find out.

STAMBERG: (Laughter) I'm game if you're game.


STAMBERG: So you've got a portable microphone there.

FLATOW: Let's take our mic out into the hallway here in-between studios.

STAMBERG: OK. Where are we going? Oh, there's the storage closet around the corner from the studio.

FLATOW: Mighty dark in here.

STAMBERG: It's extremely.

FLATOW: OK. Now, we have to get to where we can see each other crunching.


FLATOW: So I'll just stand here while our eyes get used to the darkness.

STAMBERG: Oh, yeah. OK. Who's going to chew?

FLATOW: I will...

STAMBERG: Are we both chewing?

FLATOW: I'll chew one first.


FLATOW: And then you watch and see what happens. I'll put it in my mouth.


STAMBERG: I saw it. I saw it (laughter).

FLATOW: What did you see?

STAMBERG: I saw a flash of kind of greenish light just for a fraction of a second.

FLATOW: Oh, yeah? Let me try it one more time.

STAMBERG: OK. Oh, I want to do this, too.


STAMBERG: I saw it again.

FLATOW: All right.


FLATOW: You try it. You try it.

STAMBERG: Ok. This is very bad for your teeth, though. I hope we're not encouraging...


FLATOW: Yeah. Oh, goodness.

STAMBERG: Did you see it? (Laughter).

FLATOW: It looked like a little bit of lightning, a little sparkle of lightning.

STAMBERG: I mean, nobody could explain. It's very hard to talk and chew at the same time.

FLATOW: Nobody could explain this. And they said they've done some research on it, but they really have no explanation. It's one of the mysteries of science that never gets explained.

STAMBERG: Have another LifeSaver.


STAMBERG: You think Walter Cronkite started like this?

FLATOW: (Laughter).

STAMBERG: Did you see anything?

FLATOW: Yeah, I saw it.


FLATOW: Oh. Why don't we finish up the program from in here?

STAMBERG: (Laughter) All right. Wait a minute now. But we have to do some reading, and we're not going to...

FLATOW: We need a match.

STAMBERG: I have a match.

FLATOW: You have a match?

STAMBERG: I have...


STAMBERG: ...Right in my pocket, a match.


STAMBERG: If I could only see...


STAMBERG: Oh, all right.

FLATOW: And for this evening, that's ALL THINGS CONSIDERED.

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